抄録
The enzymatic properties of crude β-galactosidases from M. phaseoli and S. tuliparum were studied from the standpoint on the pharmaceutical aspects in comparison with the properties of the enzyme from Aspergillus oryzae which is available on the market as a therapeutic agent for lactose intolerance. Optimum pH of Macrophomina and Sclerotium enzymes were 4.5 and 1.5, respectively. Stable pH ranges of the enzymes were 4 to 8.5 for Macrophomina and 3 to 6 for Sclerotium enzyme, and both enzymes were stable up to 60°and 55°for 30 min, respectively. These enzymes were not affected by addition of metal ions or reagents tested (excepting N-bromosuccinimide). The enzymes hydrolyzed lactose, and lactose in milk and dry milk with the same rate as Aspergillus enzyme. In a powder state, both enzymes were more stable than Aspergillus enzyme on standing at relative humidity (RH) of 92% and 30° and also stable to human gastric and intestinal juices in the presence of substrates. The enzymes were not affected by diluents tested. Furthermore, Macrophomina enzyme was stable for binders and disintegrators, whereas Sclerotium enzyme was completely inactivated by aerozol and sodium dodecyl sulfate (SDS) among the agents tested. Against wetting agents tested, Macrophomina enzyme was stable, but Sclerotium enzyme was stable to isopropanol and low concentration of ethanol and acetone. Both enzymes were more stable than Aspergillus enzyme under the pressure range of 0.5 to 2.0 ton. From these results, it is suggested that β-galactosidases from M. phaseoli and S. tuliparum can be effectively utilized as a therapeutic agent for lactose intolerance.
